Are both of your servers are virtualized ?
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Muhammad RajaJan 20 '13 at 10:41

Virtualization would give you the complete worry free sort of DR scenario. But it also opens a new can of worms such as .. cost.. RTO and all sorts. Usually I drive it based on clients business needs.
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Aben SamuelJan 20 '13 at 10:55

@AbenSamuel thats true but question askers intention is to have a real backup by which I can assume he want as less as possible work to do a full farm restore :)
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Muhammad RajaJan 20 '13 at 10:59

SAN replication to achieve farm recovery with least amount of work as per @TimeToShine
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Aben SamuelJan 20 '13 at 11:03

+1 and even if all SP Administrators will agree that snapshot are not the ideal solution for backup purpose, it's damn easier and ensure you don't miss any critical component. Non virtualized servers can also benefit from cold or real-time snapshots but let's have some sysadmin pro feedback (san replication sounds interesting and definitively out of my current knowledge area)
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Francois VerbeeckJan 20 '13 at 13:09